(a) Field of the Invention
The present invention relates to an auxiliary tool, more particularly to an improved winding device that has a pivot member of enhanced bending strength.
(b) Description of the Prior Art
With reference to FIGS. 1 and 2, a conventional winding device essentially comprises a hand crank 10, a securing substrate plate 11 pivotally connected with the hand crank 10, and two unidirectional gears 12 disposed between the hand crank 10 and the securing substrate plate 11. The securing substrate plate 11 is provided to secure the entire winding device in a firm position in the vicinity at where a rope is determined to be tied. The hand crank 10 is adapted to turn the unidirectional gears 12, and a pivot member 13 is used to draw and tighten the rope. Each of the hand crank 10 and the securing substrate plate 11 is provided with a pair of pivot mounting portions 100, 110 at one end thereof, the respective pair of pivot mounting portions 100, 110 being spaced apart from each other at a certain distance. Each pair of the pivot mounting portions 100, 110 is provided with co-axially aligned axial holes 101, 111. A radial retaining plate 15 is provided at intermediate portions of the hand crank 10 and the securing substrate plate 11 respectively, the retaining plate 15 being subjected to the action of a spring 14 at one end thereof so as to retain the unidirectional gears 12. The portion of the retaining plate 15 on the hand crank 10 can be manipulated manually to control the engagement and disengagement thereof, whereas the portion of the retaining plate 15 on the securing substrate plate 11 is retained in a normal state. Each of the unidirectional gears 12 has a circular axial through hole that is divided by a stop rib 121 into two semi-circular through holes 120. Each of the unidirectional gears 12 is disposed between opposite edges of the hand crank 10 and the securing substrate plate 11 and is sandwiched between the pivot mounting portions 100, 110 on either side. The pivot member 13 includes two semicircular pivot portions that are disposed parallel and opposite to each other. The pivot portions are inserted, in one operation, through the axial holes 101, 111 of the pivot mounting portions 100, 101, and the semi-circular through holes 120 of the unidirectional gears 12 to pivotally connect the hand crank 10, the securing substrate plate 11, and the unidirectional gears 12. Each pivot portion of the pivot member 13 is formed by bending and curling a plate substantially into a semi-circular structure with a cross-section having a curved face 130 and two bent portions 131 that have end portions abutting against each other in a juxtaposed manner. Distal ends of the end portions of the bent portions 131 together abut against the inner side of the curved face 130.
In the conventional winding device as described above, the pivot member 13 is a structural element that is used to bear the tightening force of tightening the rope. Although the pivot member 13 is formed by bending a plate so that it has a cross-section of the above-mentioned shape, which gives the pivot member 13 enhanced structural strength, as the end portions of the bent portions 131 abut against each other in a juxtaposed manner to abut against the inner side of the curved face 130 at one point only, the curved face 130 may easily break along the line of abutment of the bent portions 131 due to insufficient bending strength when being subjected to a large tightening force, thereby resulting in damaging of the strength of the pivot member 13. Worse, still, the pivot portions may break along an axial direction.